The machine type communication (MTC) market is a growing sector and network operators are looking for new type of services that can be provided to end users. One of the applications for MTC market is smart metering. For example MTC devices can be installed to power meters to monitor power consumptions at homes and enterprises. There are at least two main challenges to support these services in the next generation broadband technology, such as Long Term Evolution (LTE). First, the cost of MTC devices is too high compared to LTE terminals, such as smart phones. Also, the coverage for MTC terminals for the smart meter like services may need to be improved, especially assuming that those devices are likely to be installed at the basement level.
The problem of cost reduction was studied during the LTE Rel.11 timeframe in the framework of the “Provision of Low Cost MTC User Equipments (UEs) Based on LTE.” To transmit signals between devices, such as a mobile phone, a computer, or any remotely controlled machine, a radio access network (RAN) is defined to provide connections between devices and a core network (CN). RAN Working Group 1 (WG1), also referred to as RAN1, is responsible for radio layer 1, which is the physical layer of the radio interface for UE, Universal Terrestrial Radio Access Network (UTRAN), Evolved UTRAN, and beyond; covering the frequency division duplex, (FDD) and time division duplex (TDD) modes of the radio interface.
The RAN1 WG has identified several cost reduction strategies that can reduce cost of the LTE modem and break it down to the level of Global System for Mobile Communications (GSM)/Enhanced General packet radio service (EGPRS) modems. Strategies that allow substantial cost reduction include bandwidth reduction, peak data rate reduction and a radio frequency (RF) chain, half duplex operation, reduced set of transmission modes and limitation of the maximum transmit power. Almost each of these strategies leads to the degradation of the coverage characteristics for low cost MTC terminals and solutions to improve coverage beyond the current coverage characteristics need to be developed for almost every physical data and control channel.